Bayliss, Sir William Maddock

Bayliss, Sir William Maddock (bā`lĭs), 1860–1924, English physiologist. At University College, London, he investigated the mechanism of heart action, circulation, and digestion. With E. H. Starling he discovered, in 1902, secretin, a hormone produced in the small intestine, and developed a theory of hormone action. He wrote Principles of General Physiology (1914) and The Vaso-Motor System (1923).

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Bayliss, Sir William Maddock

(born May 2, 1860, Wolverhampton, Staffordshire, Eng.—died Aug. 27, 1924, London) British physiologist. He and Ernest H. Starling studied nerve-controlled blood-vessel contraction and dilation and discovered the peristaltic wave. In 1902 they showed that dilute hydrochloric acid mixed with partly digested food activates a chemical in the duodenum that they called secretin, because it stimulates secretion of pancreatic juice. This marked the discovery of hormones, a term the men coined. Bayliss also showed how the enzyme trypsin was formed from inactive trypsinogen and measured precisely the time it took to digest protein. His recommendation of gum-saline injections for wound shock saved many lives in World War I.